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Is your Vitamin D Status Optimized to Maintain your Health?

By Michael McBurney

Without dietary supplementation, many people fail to eat enough foods rich in vitamin D or get enough direct sunlight on skin surfaces to maintain optimal serum 25(OH)D levels. With suboptimal vitamin D levels, we can feel tired, be more prone to falls, minor respiratory infections and other non-communicable diseases. Based on abnormalities in bone maintenance and accretion, the Institute of Medicine defined serum 25(OH)D concentrations below 30 nmol/L as deficient and 50 nmol/L as adequate.

Mitri et al (2014) found a number of metabolic syndrome risk factors increased with decreasing 25(OH)D levels. The average plasma 25(OH)D tertiles were 30, 50 and 75 nmol/L. Also based on nationally representative US data, Guixiang and colleagues reported a reduced risk of death among hypertensive adults with 25(OH)D levels above 73 nmol/L (vs lower levels). These observations using endpoints other than bone health provide evidence that optimal serum 25(OH)D levels may be nearer 75-80 nmol/L than 50 nmol/L.

Overall, these studies tell us two things. There is accumulating evidence that maintaining serum 25(OH)D levels approximating 75-80 nmol/L is beneficial. Most people are failing to achieve these targets through diet and sunlight. Did you take a vitamin D supplement today?